really don't have many disappointments from the trilogy, would have loved to see more of Iron Mans rogues, ie: Madam Masque, Living Laser, Ghost, Spymaster, Crimson Dynamo & Titanium Man.
Maybe if a 4th film comes to pass some of these villians will be used, but who knows, up to Marvel and RDJ.
Iron man 2 while good, could have been better if not for what I felt was an Avengers set up, just felt like Blackwidow was put in to introduce her for the Avengers, she really did not add much.
Otherwise, I am thrilled with 3 awesome movies.